MySQL 8.0

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CREATE TABLE `elbat`
             (`Transaction ID` tinyint,
              `Sender` varchar(1),
              `Receiver`varchar(1),
              `Sender Receipt` tinyint,
              `Receiver Receipt`tinyint);
INSERT INTO `elbat`
            VALUES (1, 'A', 'B', 2, 4),
                   (2, 'C', 'A', 5, 1),
                   (3, 'B', 'C', 5, 1),
                   (4, 'C', 'B', 3, 4);
SELECT `Last Transaction`.`Sender or Receiver`,
       CASE `Last Transaction`.`Sender or Receiver`
         WHEN `elbat`.`Sender` THEN
           `elbat`.`Sender Receipt`
         WHEN `elbat`.`Receiver` THEN
           `elbat`.`Receiver Receipt`
       END `Last Receipt`
       FROM (SELECT max(`Transaction ID`) `Transaction ID`,
                    `Sender or Receiver`
                    FROM (SELECT max(`Transaction ID`) `Transaction ID`,
                                 `Sender` `Sender or Receiver`
                                 FROM `elbat`
                                 GROUP BY `Sender`
                          UNION ALL
                          SELECT max(`Transaction ID`) `Transaction ID`,
                                 `Receiver` `Sender or Receiver`
                                 FROM `elbat`
                                 GROUP BY `Receiver`) `Last Transaction`
                    GROUP BY `Sender or Receiver`) `Last Transaction`
            INNER JOIN `elbat`
                       ON `elbat`.`Transaction ID` = `Last Transaction`.`Transaction ID`;


Sender or Receiver
Last Receipt


A
1

C
3

B
4